Support the higher part of a ship (6)
I believe the answer is:
uphold
'support' is the definition.
(I know that uphold is a kind of support)
'higher part of a ship' is the wordplay.
'higher' becomes 'up'.
'part of a ship' becomes 'hold' ('hold' is part of 'ship').
'up'+'hold'='UPHOLD'
'the' acts as a link.
(Other definitions for uphold that I've seen before include "Support, maintain" , "'Support, the law say (6)'" , "Sustain and endorse" , "Of appeal court, endorse earlier decision" , "Confirm or support, say a verdict" .)